The United Nations refugee agency, UNHCR, is working with Pakistani officials to investigate complaints about police harassment of Afghan refugees in Pakistan. The U.N. agency has said most of the alleged incidents have occurred in two cities.

Refugee agency officials said that police in the cities of Rawalpindi and Islamabad have recently arrested more than 400 Afghans and forced other Afghans to stay in their homes, warning them they would be jailed if they were seen on the streets.

The refugees said police in the two cities have carried out raids in slum areas inhabited by Afghans and have tried to extort money, threatening the refugees with jail if they fail to pay.

UNHCR spokesman Ron Redmond said the refugee agency officials met on Thursday with a task force set up by Pakistan's interior ministry that is investigating the charges made by the refugees.

"UNHCR expressed deep concern that, at a time when over 650,000 refugees have already repatriated from Pakistan in less than three months, coercive measures were counterproductive, and could impact negatively on the voluntary repatriation from Pakistan," Mr. Redmond said.

Mr. Redmond has said that Afghan refugees in other parts of Pakistan have also reported incidents of police harassment. "In Muree, a town in the hills to the north of Islamabad, a group of around 100 Afghan Tajiks were apparently forced out of their homes by plainclothes police. Some were arrested. The rest could see no other alternative but to hire trucks and go back to Afghanistan," he said.

Refugee agency officials do not believe the incidents are part of any government policy but appear to be carried out by individual police officers acting on their own. The officials speculate that the harassment may be related to the killing earlier this month, May 8, of two policemen in Rawalpindi. The police suspect Afghan robbers are responsible for the murders.